Transformant bacterial culture capable of expressing heterologous protein

Abstract

The Specification discloses: 1. Recombinant microbial cloning vehicles comprising heterologous DNA coding for the expression of mammalian hormone (e.g, somatostatin) and other polypeptides, including plasmids suited for the transformation of bacterial hosts. The latter incorporate a regulon homologous to the host in its untransformed state, in reading phase with the structural gene for the heterologous DNA; 2. Cloning vehicles coding for the microbial expression of a protein variously comprising (a) a polypeptide hapten and additional protein sufficient in size to confer immunogenicity on the product of expression, which may find use in raising antibodies to the hapten for assay use or in the manufacture of vaccines; and (b) a desired polypeptide product and additional protein from which the desired product may be cleaved; and 3. Methods of preparing synthetic structural genes coding for the expression of mammalian polypeptides in microbial cloning systems.

I claim: 
     
       1. A transformant bacterial culture cloned from one or more bacteria each comprising a recombinant microbial vehicle, said vehicle comprising: a regulon, a structural gene coding for the amino acid sequence of a desired heterologous polypeptide and one or more termination codon(s) wherein a DNA sequence coding for additional protein is interposed between said regulon and termination codon(s) without altering the reading frame of said structural gene such that a precursor protein comprising both the amino acid sequence of the desired polypeptide and that of additional protein results from expression, the additional protein comprising a selective cleavage site adjacent the amino acid sequence of the desired polypeptide; the members of said culture being capable of expressing said precursor protein.   
     
     
       2. A transformant bacterial culture according to claim 1 wherein the desired polypeptide contains no similar selective cleavage site. 
     
     
       3. A transformant bacterial culture according to claim 1 wherein the recited elements of the plasmid are sequenced as follows: (regulon)-(codons for additional protein)-(codons for desired polypeptide)-(termination codon(s)). 
     
     
       4. A bacterial culture comprising E. Coli. RR1 (pSOM1). 
     
     
       5. A bacterial culture comprising E. Coli. RR1 (pSOM11).